03/14/2017 01:19 EDT | Updated 03/20/2017 04:41 EDT

Federal Government Takes Next Step In Purchasing Super Hornet Fighter Jets

OTTAWA — The Liberal government has taken the next step towards buying 18 Super Hornet fighter jets on an interim basis, a purchase it hopes to make official by year's end.

The government sent a letter to the U.S. government on Tuesday outlining exactly what it needs in the warplanes, when it needs them, and what type of economic benefits Canada expects in return.

Aerospace giant Boeing will use those requirements to draw up with a formal proposal by the fall, with the government hoping for a contract by the end of 2017 or early 2018.

The Liberals have said any deal will be contingent on getting the Super Hornets at the right price, on the required schedule and with the right economic spinoffs.

super hornet

A U.S. Navy F/A-18 Super Hornet fighter lands onto the deck of the USS Ronald Reagan, a Nimitz-class nuclear-powered super carrier, during a joint naval drill between South Korea and the U.S., in the West Sea, South Korea, Oct. 14, 2016. (Photo: Kim Hong-Ji/Reuters)

"We will assess whether an interim Super Hornet fleet purchase will help ensure Canada remains a credible and dependable ally for many years to come," Defence Minister Harjit Sajjan said in a statement Tuesday.

The agreement must also be approved by the U.S. Congress.

The government announced in November its plans to augment Canada's aging CF-18 fleet with the new Hornets until a full competition to replace the CF-18s can start in 2019.

The Liberals say the Super Hornets are needed because the air force doesn't have enough jets to be ready to defend North America and contribute to NATO at the same time.

Interim fleet more expensive: retired officers

But a number of retired military officers have called for an immediate competition, warning an interim fighter fleet will be more expensive and hurt the military in the long run.

Sources have said the Liberals plan to purchase the Super Hornets using money the previous Conservative government originally set aside for F-35 stealth fighters.

But they will almost certainly need to find additional money to replace the CF-18s, either through their new defence policy or by cutting other projects.

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